Sound-box structure



May 22, .1923. 1,455,972 C. SCRABIC U SOUND Box STRUCTURE Filed April 28,A 1920 ,Tm "im I vf v tlllllllll-.I

' which the follwingis a 'Patented May 22,

siren srjArels PATENT ortica.'

CARL scRABIc, or URBANA, omo

Application mea'Aprn 28,1920. serial No. 377,221. f

To all whom it may conce/m:

Be itknown that CARL ScRAnic, a citizen ofthe United States, residing at Urbana, in the county of Champaign and State of Ohio, has inventedcertain new and useful Improvements nSound-Box Structures, of

specification.

This invention relates broadly to--talking machines, and has particular reference to the sound reproducing mechanism thereof, l the object of the invention being fundamentally to provide a sound box of such construction that the same will automatically act to position itself in such manner that its needle or stylus will be properly centered in the groove of a record with which the sound box is employed, the construction 'being such that the stylus will be located in the center of gravity of the sound box and pivots,

will be maintained in proper relationship lwith the record irrespective of position variations which the latter may assume vduring its rotation. y

Another object of the invention resides in the provision of an improved connection or mounting between the tubular out-let end of a sound 'boxand the forward end of a tone arm, said mounting consisting of aplurality of concentric rings which are provided wth independent angularly located the arrangement of the rings and pivots beingfsuch that the sound box'may be freely suspended so that its stylus will for by virtue of the weight of the sound box, be maintained in proper engagement with record grooves, the pivot construction allowing lateral movement on the part of the sound box and also for similar vertical movement, said mounting, allowing the stylus of the sound box to be properly positioned grooves even when the record is`not rotating on a true'horizontal plane. Y l

further object of the invention resides in constructing. the sound box so that the same may be adapted for-reproducing pui- :the sound box,

poses in connectionv with both lateralandv vertical c ut records and to provide adjustable weight means in conjunction with whereby its effective weight may bevaried to properly adapt the same to the particular type of record with which i With these and otherobjects in `view, as will appear as the description proceeds, the invention .accordingly consists in the novel features Aof construction, combinations ,ofi

elements and arrangement of parts, hereinafter to fully described and to have thescope thereof pointed out in the appendedclaims.

lar characters of reference vdenote like and corresponding parts: 'y l Figure 1 is a vertical sectional view taken tion Iand its cooperative mounting. Figure-2 is,a front elevation thereof."`v Figure 3 is a horizontal sectional ,v iew taken through the mounting on the line 3-3 of Figure 1.

Figure 4 is a detailed view disclosing more particularly the construction of the upper part of the sound box stylus, and,

Figure 5 is a horizontal sectional view disclosing the weight adjusting mechanism. In the accompanying drawings there'h'as been shown for purposes of illustration the deck 1 of a talking machine. This deck is provided with the usual rotatable turn table or record support 2 which is operated by means of a'motor driven spindle 3. Arecin the usual manner upon. the upper'surface of the turntable for cooperating with the sound box 5 of the talking machine. As

ord of any suitable type 4 may be imposed.

through the improved sound box construcusual, the sound box'is carried by the'outer end Aof a swinging tone arm 7, the latter beingmounted for pivotal`movement within a bearing 8 provided upon the' deck 1. It

vwill be understood that the stylus 9 f'the i sound box is adapted to engage in the usual manner with the grooves of the record 4, but

bowl or shell .10* which is formed toI terminatein Aa reduced and shouldered.

neck portiony 11 which is in direc-t communication with a wooden'supporting tube 12, the'upper end-of the latter being connected `in a manner to be hereinafter'describedwith the outer end of'the tone arm 7. To-con neet the neck portion 114 w`ith lthe latter is provided with afixcd metallic cup 13 upon its lower end, which cup is formed with an. out-'turned flange dispns'ed for swiveled engagement with an in-turned .flange 14, formed on a metallic ring 15,

-sound box 5l consists of a woodenthe tube 12, f

which -is carried in a threaded manner'by' the shell Il0, and a packing 16 may beinterposed between the adjoining surfaces of the shell and the tube 'l2 in order to in-- sulate the sound-conduit therein from the metallic parts` 14:. and v15. Obviously,A

.through this construction, the position of the sound box may be. altered by rotation,

` in'ordery that saidsound box may be adapted to the different types of records.

Iny this instance, the lower annular edge I of the shell y10 is provided with metal an'- nulus 17, which is suitably secured in position in connection with the shell many desired manner. The interior-*f thc annulus isprovided with a recess 18 which is closed' .by means of an adjustable ring 19 carried by the annulus.

cess 18 yis a plurality fot' gaskets 20 be Positioned within the retween certain of which there is 4clamped vthe diaphragm 21 of the soundvbox. This diaphragm is preferably formed'from metal or an equivalent substance and is of dish -formation instead of being of the usual flat construction. The center of the diaphragm' is arranged for cooperation Withthe free end 22 of an oscillating stylus 23, and it will be seen, upon reference to Figure 1 that the diaphragm is' preferably 'formed with a plurality of undulations.' These un? d'ulations. are `quite marked at. the center of the diaphragm and gradually decrease in depth toward thev outer circumferential edge` of thev diaphragm. This construction results -in increasing the vibratory --area of the diaphragm and also adapts the latter to YIl() entire areato' clearly reproduce the vibra the natural .sound wave curvatures. yThis construction may be likened to the(` dro ping-'of a pebble in a body of water, `froml which it.will be observed that the ripples produced are lmost pronounced in the water in which the pebble is dropped, and that the rip les gradually 'decrease -in depth in circuinv erent-ialwaves or undulations from that particular point. In other words, the

construction of thel diaphragmv21is such that the. 'same will adapt .itself over its tions delivered thereto by reason vof its engagement with the stylus 9.

'The stylus itself` 'is carried by means of a' conical casingv 24, which,v latter. has its n outer circumferentialedge .secured in place between certain of the gaskets `20.v rl`he` apex ofthe casing 24 is. provided with a bearing member 25, the latter carrying pivot screws 26 by means of. which 'the stylus is pivotally mounted for substantiallyfree swingingmovement. Thelower end of .the stylus may be equipped with the usual thumb screw 27 by means of which a needle or the like 28 may be detachably connected` therewith. T` 'e upper end of thestylus 23 is curved an reduced in thickness, as is indicated by the numeral 29. This contessera.'

struction results in rendering the stylus ex-A tremelysensitive 'and' susceptible 'to the faintest movements created -bythe needlel 28 with .the undulations4 of the record 4."

The sound box is cdnnected with thezfree end v.of the tone arm' 7 byme'ans of the mounting 30. lThis mounting preferabl consists of a ball bearin 'raceway 31 whic is provided inthe en of the tone arm. Freely mounted for -rotation within the raceway31 is a Inet-allie annulus 32.- This annulus carries concentrically within the same va ring 33, which, in turn, receives the concentric `upper en dof the tuba 12. The latter isprovided with an offset flange upon its upper end which retains 'in position da wear collar 34. As is clearly shown in Fig- I ure 3, the annulus 32 is provided with a pair 4of 4dia-metrically aligned pivot screws 35 whose point ends are arranged to engage with `bearing Adepressions formed in the outer edge of the ring 33. When theparts are positioned in the manner shownv .in-

Figure 1, it will be manifest thatzthevprovision of the screws 35 will permit of upward or vertical oscillation on the part .of

the sound box, 33 being suitably ,curved\so that the same will -be ypermitted to oscillate within the confines of .the annulus 32. and without.l binding upon the latter. I Similarly, the

J'ing 33 is provided with pivot Iscrews 36 which are disposed to engage withbearing theouter edge .of the ring depressions 'formed inthe collarI 34. These I screws 36`are located at right angles tothe screws 35 and hence are capable of permit.

of'v oscillatory laterall motion onv the ting vpart ofthe sound box structure.A The outer face ofthecollar 34 is curved onal suitable rad-ius to prevent said collar when*` beingl oseillated from binding itself in engagement with the. inner edge of the ring 33. The upper end-ofthe tube 12, of course,

"opens freely into the. tone arm '7, so thata sound conduit may be provided through the sound box structure into the interior of the tone armf it'will be manifest that a sound box is provided .which will automatically maintain 1n proper relationship with a cooperative t. record. Itis aV well known fact that records'v By 'virtue of the construction described, i

the sound box may rotate horizontallyv by-l 2 Adisclosed that 'of these movements serve`to allow the stylus lFurtherr'nore,

ure 1. While in this position, the mercury will flow toward the lower part of the ring,

. line position by latter being carried by tion bearings provi annulus sound box that will' cause `the latter and reason o"f the. engagement of the annulus 3 with the ball bearing raceway 31, and this movement may take place with b`ut a-mini-` mum of friction by reason of the anti-fricmovement of the sound box is taken care of by the pivot screws 35 carried 32 and lateral movement is provided o'r by reason o; the screws 36. -All construction of a sound box to automatically adapt itself to variations inthe operative position of a record, and direct-ly`tend to eliminate undue friction between the stylus and the walls defining the grooves of a record. This results in a reduction in friction between the stylus and record and hence an absence of grating or scratching noises in the finally reproduced music. the .sound box and tone arm construction provides a sound conduit having resonant walls preferably formed trom wood, a feature which also tends to minimize discordant notes. It will be observed that the needle 28 is positioned exactly in the center of gravity of the sound box and not to one side thereof, this feature insures proper engagement between the needley and the record grooves and also ltends to minimize undue friction. y

Preferably, the tube 12 is provided with a pivoted hollow ring 37, in which a suitable bo`dy of mercury is confined. The ring 37 isv pivoted centrally as at 38 to` the tubo 12 and by 4vmeans o f aspring 39 said ring is maintained in the position 'shown in Figthus causing its weight to be exercised pn the side offthe center of gravity of the the latter to oscillate more rmly toward the record. However, when the soundbox is given a quarter of a turn to provide for vertical cut records, said ring 37- will be moved to the dotted means of the cam 40, the the upper portion of the sound box shell 10. vThis results in causing the mercury to flow to the opposite side of the center of gravity 'of the soun box, 'thus tending to lighten the weight of rendering the same particularly adaptable for the reproduction of ver- 4tical cut records.

The presence of therng ded Further, vertical by the.

lat right angles to. the

is the result of investigations (which have when lateral cut records are employed, a sound box structure of greater weight should be utilized than when vertical cut records are to be reproduced. By the prsence of the ring 37, this change in weight is automatically accomplished and a sound box- :structureV is provided which may be used with efficacious results in connection with either type of record.

What is claimed is:

1. In a talking-machine, a tone arm, a sound box connected with the free end of said tone arm, the connection between said tone arm and sound box being formed to constitute an annulus mounted for rotation in a bearingconnected with said tone arm, a ring member located within said annulus and pivotally mounted witherespect thereto and an extension formed upon the upper end of said sound box and having pivotal connection with said ring member; the pivotal connection between said ring member and sound box being located substantially pivotal connection between the annulus and ring member.

2. In reproducing mechanism fortalking i machines,a tone arm, a sound box rotatably records, amounting formed with said tone arm for effecting-a swinging suspension oi said sound box, and automatically operated d eo means located between the tone arm an sound box capable of varying the elfective ressure upon 'the stylus of said sound box 1n accordance with the operative position of the latter. i

3. In sound reproducing mechanism for talking machines, a combination with 'a swinging tone arm, of a sound box movably suspended from the free end of said tone arm, means permitting of the rotation of.

said sound box relative to said tone -arm to adapt the same to both verticalv and lateral cut records and an adjustable fluid container cooperative with said sound box and capable of varying the e'ective pressure uponV stylus of the latter in accordance with the d operative position occupied by the sound box.

testimony whereoi I affix my signature.

CARL SORABIC.

the 

